1. Field of the Invention
This invention relates to a foamed coaxial cable and a multicore cable using an insulation formed of a foamed material.
2. Description of the Related Art
A high speed transmission foamed coaxial cable is known that uses a low-permittivity insulation formed of a foamed material (See e.g. JP-A-2003-141944).
For example, a foamed coaxial cable 21 as shown in FIG. 2 is known that is composed of a pair of signal conductors 2, an insulation (or formed insulation) 3 which is of a foamed material for collectively covering the periphery of the signal conductor 2, a non-foamed skin layer (or outer skin layer) 4 which covers the periphery of the insulation 3, and a shield conductor 5 disposed on the periphery of the skin layer 4.
The other related art may be JP-A-2010-080097 and JP-A-2008-293862.